The prior art is documented with numerous examples of closure assemblies for directly engaging together individual pieces, panels or layers without the requirement for separate fasteners, adhesives or the like.
One example is the connector structure of Rittenhouse, U.S. Pat. No. 8,713,764, which is removably attached an object to a support platform and includes an elongated, rigid material base having a locking assembly disposed thereon and including a retainer and a gripping member. The gripping member is movably connected to the retainer and disposable relative to the base into both a locking orientation and a release orientation, wherein the locking orientation comprises a predetermined portion of the gripping member disposed in gripping, at least partially penetrating relation to an exposed surface of a corresponding part of either the support platform or the supported object. An activating member is connected to the gripping member and movable therewith, wherein positioning force exerted on the activating member will selectively dispose the gripping member between the locking and release orientations.
U.S. 2017/0350139, to De Rick et al, teaches a set of mutually lockable panels with a first panel having an edge including a male part and a second panel having an edge including a female part for receiving the male part of the first panel in unlocked condition of the panels. The male part has an outer side which, in locked condition of the panels, is directed to the second panel in a direction substantially parallel to the front face of the first panel, and an opposite inner side which is provided with a locking surface. The female part comprises a locking member, which is pivotable about a pivot axis that extends substantially parallel to the edge of the second panel and an actuator for rotating the locking member from its unlocked condition to a locked condition of the panels.
A further example from the known art includes the protective case with over-center flap closure and stylus holder of Denike et al. U.S. 2017/0188676 disclosing a sleeve portion (4) having a sleeve opening (17), a closure portion (6), and a hinge (8) connecting the closure portion (6) to the sleeve portion (4) adjacent the sleeve opening (17). A stylus cavity is formed within the sleeve portion. The opening of the stylus cavity is adjacent the sleeve opening. The hinge (8) is adapted to allow the closure portion (6) to move from a first position away from the sleeve opening and stylus cavity opening to allow the device (22) to be inserted into the sleeve portion (4) and the stylus to be inserted into the stylus cavity and a second position where the closure portion (6) is positionable over an end of the device (22) and over the stylus cavity opening.